In a large pot, sort through green lentils for any hard debris or rocks.
Add 4 cups of water and 1 bay leaf and bring everything to a boil.
Cover the pot slightly, leaving the lid ajar, and simmer gently for 25-30 minutes. Lentils are ready when the water is fully absorbed and lentils are tender to the bite.
Marinated Lentil Salad:
In a bowl, combine all dressing ingredients - olive oil, red wine vinegar, lemon juice, minced garlic, mustard, salt and pepper.
Add in the diced onion to allow them to marinate while you prepare the other ingredients.
Throw in lentils, shredded carrots, diced celery, chopped parsley and diced green onions. Stir well and adjust salt and pepper to taste.